1. Field of the Invention
The present invention relates to a mechanical apparatus for pumping air into closed containers. More particularly it relates to a hand powered portable lightweight industrial type air pump for high-volume low pressure air transfer to air inflatable structures. Specifically, it relates to a high-volume low pressure hand operated air pump for large size multiple person white water/river rafts.
2. Description of the Prior Art
The use of a hand pump in one configuration or another for the purpose of pumping air into an inflatable object is well established in the prior art. However, despite the numerous designs, structures, and forms disclosed by the prior art, which have been developed for the accomplishment of the various related objectives, purposes and requirements, the use of hand actuated air pumps heretofore devised and utilized consist basically of familiar, expected, and obvious, configurations, combinations, and arrangements which are too numerous to consider. The two most universally utilized examples of these types of pumps are the ubiquitous T-handled bicycle pump and the step-on squeeze pumps.
The high-volume low pressure air pump contemplated according to the present invention departs substantially from the conventional concepts and designs taught by the prior art, and in doing so, provides an apparatus primarily developed for the purpose of inflating relatively large collapsible structures such as white water/river rafts as described above, but it accomplishes the result with a new, improved, and specifically unique apparatus.
There are numerous and obvious inefficiencies and disadvantages inherent in the known types of hand or foot operated air pumps presently existing in the prior art such as the fact that the bicycle pumps are heavy and corrode, while plastic foot powered pumps easily break or disintegrate, and both are low volume air pumps. The present invention provides a new lightweight, compact, durable, inexpensive construction wherein the same can be utilized to inflate relatively large collapsible structures while requiring only minimum storage space where such space is at a premium such as when packed on-board a white water/river raft.
The general purpose of the present invention, which will be described hereafter in greater detail, is to provide a new high-volume low pressure hand-operated air pump apparatus and mechanism which has many of the advantages of the old-style reliable air pumps mentioned above and specific novel features that result in a new lightweight high-volume low pressure air pump which is not anticipated, rendered obvious, suggested, or even implied by any of the prior art of hand operated air pumps, either alone or in any combination thereof.
The present invention is a high volume, low pressure air pump comprising an elongated tube body having a guide hole located proximate to a first end thereof and disposed on the cylindrical axis of the tube for surrounding the shaft of a plunger and allowing the intake of air into the tube through the guide hole. The body forms an air chamber between the internal end of the plunger shaft and a second end of the tube.
A plunger shaft is disposed partially internally of the tube body and extends through the guide hole of the body and is formed to reciprocate therein. The shaft includes a handle secured at a first externally exposed end thereof. The length of the shaft is longer than the length of the body.
An air intake floating seal is secured to the internally disposed second opposite end of the shaft. The air intake seal includes a piston secured to the second end of the plunger. The piston has its longest cross-wise dimension shorter than the internal diameter of the tube body whereby the plunger can freely reciprocate in the tube and air can bypass around the edges of the piston as the plunger is withdrawn from the body.
A circular seal is engaged in a restrained floating relation to the piston on the air chamber side thereof and has a first side comprised of closed cell polyethylene plastic foam. The first side is larger in diameter than the internal diameter of the tube body. The foam side of the seal is disposed in facing relation to the piston on the air chamber side thereof and is frictionally engaged in sealing relation with the internal wall of the tube body. The circular seal has a second plastic stiffener side smaller in diameter than the internal diameter of the body and forms a backing to the foam side of the seal on the air chamber side thereof. The stiffener side of the seal is comprised of the same material as the closed cell foam and is integral thereto. The circular seal has air passages formed there through which are closed when the seal is pressed against the piston,
A circular seal cage is secured to the piston on the air chamber side thereof. The cage has at least one central pedestal forming at least three radially outward projecting cantilevered bridge ring seal retainers disposed at equally spaced positions from each other. The retainers are each also equally spaced from the piston a distance greater than the thickness of the circular seal to permit movement of the seal away from the piston a predetermined distance parallel to the cylindrical axis of the tube. The circular seal is captured between the outward projecting cantilevered cantilevered bridges on the air chamber side of the piston and encircle the outer periphery of the central pedestal.
A check valve is disposed proximate to the second end of the tube and has an air flow block side and an air flow discharge side. The air block side is disposed to communicate with the air chamber of the body. A flexible air delivery tube connected to the air flow discharge side of the check valve.
The more important features of the invention have been broadly outlined above in order that the detailed description thereof which follows may be better understood and in order that the present contribution to an improvement in the art may be better appreciated. There are additional specific features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
With respect to the claims hereof, and before describing at least one preferred embodiment of the invention in detail, it is to be understood that the invention is not to be limited in its application to the details of construction and to the arrangements of the components which are set forth in the following description or illustrated in the drawings. The invention is capable of being created in other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed here are for the purpose of description and should not be regarded as limiting.
As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other forms, structures, methods, and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions in so far as they do not depart from the spirit and scope of the present invention.
Further, the purpose of the appended abstract is to enable the United States Patent and Trademark Office, and the public generally, and especially scientists, engineers, and practitioners of the art who are not familiar with the patent and legal terms or phraseology, to determine quickly from cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the specification, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
It is therefore an important object of the present invention to provide a high-volume low pressure hand operated air pump.
It is another object of the present invention to provide a high-volume low pressure hand operated lightweight air pump made from low-cost commonly available materials and utilizing simple construction techniques.
It is a further object of the present invention to provide a high-volume low pressure hand operated air pump which is of simple construction, reliable, durable, and corrosion proof.
It is still another object of the present invention to provide a high-volume low pressure hand operated air pump using a double density polyethylene plastic air valve seal having a closed cell plastic foam sealing surface which seals with the air tube and requires no lubrication.
And it is yet a further object of the present invention to provide a high-volume low pressure air pump which can be assembled almost exclusively by the use of room temperature curing glue.
Other objects and advantages of the present invention will become apparent when the method and apparatus of the present invention are considered in conjunction with the accompanying drawings.